How do I get sepiroth

I’ve been playing smash the past few months and unlocked about 60 characters and got a notification saying all characters unlocked. Earlier this week I went to a tournament with professional players and I saw so many new characters. I couldn’t make out the names except one, sepiroth. I looked up online and I saw the options were to play world of light or classic. I played a few hours and I still haven’t got any new characters. I don’t even know if I am doing the right thing. Can you please tell me what I should do? If I am being honest, I don’t really enjoy world of light that much so is there an alternative?